Automatic conveyor filling system for blast furnaces



964 R. A. POWELL ETAL AUTOMATIC CONVEYOR FILLING SYSTEM FOR BLAST FURNACES Filed July 11, 1961 3 Sheets-Sheet 1 INVENTORS. 20;:541. a. fDwZLLL, am e. RICE Jan. 14, 1964 R. A. POWELL ETAL 3,117,682

AUTOMATIC CONVEYOR FILLING SYSTEM FOR BLAST FURNACES Filed July 11, 1961 s Sheets-Sheet 2 a tgnonuorcu i Z INVENTORS. Rom-44 4. Pare/7511b, Om/V 2. RICE.

United States Patent 6 3,117,682 AUTQNA'EZC CGNVEYGR FELLBTG SYSTEM FQR BLAST FURNACES Russell A. Powell and Owen R. Rice, Pittsburgh, Pa, as-

signors to Koppers Company, inc, a corporation of Delaware Filed July 11, 1961, Ser. No. 123,312 2 Claims. (ill. 21418) This invention relates to a material handling and charging system for blast furnaces, and more particularly, to a b lt charging system for automatic layering of coke, limestone, ore and sinter in blast furnaces, to obtain the same conditions now existing for furnace filled by the conventional skip hoist system. The invention is also suitable for a mixed charge system by a modification thereof as hereinafter described.

A particular object and advantage of the present invention is to provide a more efficient charging system for blast furnaces which is simple in construction and operation, which is economically feasible with known automatic electric controls, and which avoids complex material handling difiiculties at conventional junction points.

in the processing of ore in a blast furnace, it is the customary practice to employ a skip hoist mechanism for charging the furnace in sequence with ore, stone and coke. For this, skip cars are connected together through their operating mechanism in counter-balancing relation and arranged so that when one car is traveling upwardly along its track toward the top of the furnace the other car is traveling downwardly along its track toward the charging pit. During each of a plurality of steps of a cycle of the charging sequence, the skip car in the charging pit is loaded with a predetermined, measured quantity of preselected charging material whereafter the loaded skip car is hoisted to the top of the furnace and the material dumped onto a cone-shaped small bell in the distributor hopper. In order to evenly distribute the large and small particles of the charging materim and to preselect and control the distribution of the difierent types of charging material in the furnace, the distributor hopper is rotated after each skip load has been dumped therein whereafter the small bell is lowered to discharge the material onto a cone-shaped large bell. After a preselected number of loads have been deposited on the large bell in a desired distribution, the latter is lowered to discharge the material into the furnace.

For high pressure up to pounds furnace top pressure small and large bells are provided with alternately operable relief and equalizer valves to facilitate opening of the bells. The relief valves connect the spaces between the bells to the atmosphere while the equalizer valves connect the spaces between the bells to a source of gas from the interior of the furnace. The respective valves when opened equalize the pressures on opposite sides of the bells to facflitate opening them. The valve operating mechanisms are interlocked with the bells so that the relief valves can be opened when the large bells and equalizer valves are closed and the equalizer valves can be opened when bells and relief valves are closed.

It is necessary that the charging sequence of ore, stone, coke, that is dumped into the distributor hopper, be capable of controlled variation as desired. To attain this, a charging control system afiords preselection of a desired charging sequence program and modification thereof at will by addition of extra loads of desired materials.

In accordance with the present invention, in lieu of skip hoist charging, a combination of equipment for automatic belt charging of blast furnaces is provided which is especially suitable for use with blast furnaces operating under high pressures up to thirty pounds top pressure and provided with three charging hoppers to conserve such pressure during charging the furnace with material in conventional order suitable for layer filling. With such high top pressure, the rate at which the feed material is consumed is much higher than at lower pressures below five pounds top furnace pressure, and it is desirable to provide a simpler and less complex arrangement of parts than the skip hoist system for charging the hoppers more often and more rapidly than can be done with skip hoists to maintain the higher rate of consumption of material in the blast furnace as is necessary for operation with such much higher internal gas pressure in the blast furnace.

Accordingly there is provided an automatic belt conveyor system for filling blast furnaces with three feed hoppers at the furnace top, which system comprises a surge hopper for the first filling hopper; a single endless belt conveyor disposed in a single line, without transfer turns and junction points, extending from below yard or ground level on an incline up to the surge hopper, located above the first bell at the top of a blast furnace; readily accessible equipment above yard level for feeding ore, limestone and coke fromstockbins above yard level in the area of the feed end of the single belt conveyor; and a specific arrangement of bins, Weigh hoppers, and feeders for the furnace.

The surge hopper is equipped with a gate for use when dumping the top hopper to prevent the closure for the top hopper, such as, the top bell from closing upon a lump of material which would hold the hopper open.

The single belt delivery of materials avoids material handling difficulties that occur at conventional junction points with multiple belt delivery.

The basic arrangement of symmetrical stock house for charge materials lends itself readily to supply charges in proportions of 60 to line sinter and 40 to 20% screened ore. The number of bins can be modified to suit other proportions as required or to provide additional storage capacity.

The arrangement of equipment is suitable for layer filling to obtain the same conditions now existing for furnaces filled by the conventional skip hoist mode of operation. The combination of equipment is also suitable for a mixed charge system by slight modification.

The invention will appear more fully from the following detailed description when the same is read in conjunction with the accompanying diagrammatic drawings. It is to be expressly understand, however, that the diagrammatic drawing is not intended as a definition of the invention but is for the purposes of illustration only.

Referring to the drawings:

FZGURE 1 is a vertical side elevational view of a blast furnace equipped with material handling apparatus in accordance with the present invention;

FlGURE 2 is a top plan view of the same;

FIGURE 3 is a detailed vertical elevational View of the blast furnace;

FTGURE 4- shows the basic arrangement of symmetrical stock house bins for material fed to the belt conveyor for top charging blast furnaces;

FIGURE 5 is a vertical cross-sectional view on line VV of FIGURE 4;

FIGURE 6 is a vertical cross-sectional view on the line of FIGURE 4;

FIGURE 7 is a horizontal sectional view on the line 7-7 of [FIGURES 5 and 6.

The arrangement of equipment as shown on the drawings is designed for automatic layer filling blast furnaces through a surge hopper for three top charging bells, as described in US. Patent 2,516,190, for operation at top pressures up to thirty pounds per square inch. The invention is not limited in all its aspects to use with such a single surge hopper 29 for the furnace, since it may be 3 desirable to provide additional surge capacity at the top of the furnace by arranging two surge hoppers side by side to be alternately discharged and refilled.

As shown in FlGURES 1 to 3, the blast furnace measures about 172 feet in height from yard level 11, with the iron notch 12 at a level of about 22 feet up from the level of the yard. The main body of the furnace then rises about 110 feet from the iron notch 12 to the top 1.3 of the furnace proper, where the top of the lower section 14 of the lower hopper 15 for the lowest bell No. 3 rests on the top 13 of the furnace. From the top 13 of the furnace, the three hoppers rise about 40 feet, making a total elevation of 172 feet from yard level for raising the ore, stone, and coke in charging the furnace.

For the more rapid flow of said material to said elevation, such as is required with furnaces operating at high top pressures up to p.s.i.g., there is employed a single endless belt conveyor 16. As seen in FIGURE 1, the major portion 17 of the conveyor is inclined along a single line, without transfer junctions, on an angle to the horizontal corresponding to the normal angle of repose of the material to be conveyed, preferably on an angle 18 between 14 and 16 degrees from horizontal at yard level 19. The belt, as shown extends for 720 feet from just below yard level 19 to a point over the top of the surge hopper 21 The belt 17 has a lower feed end extension 21 disposed about 15 feet below yard level to facilitate loading the belt with the material for the blast furnace by means of feeding equipment 52 located at yard level for convenience of access in repair, replacement and maintenance of the feeding equipment.

The material to be fed to the blast furnace is stored in a series of stock house bins 23 for sinter, ore, limestone and coke, which bins are charged at their tops and discharge to the feeding mechanism at their bottoms. The bins are mounted at yard level 19 so as to have their bottoms a suflicient distance above yard level to leave room for the feeding mechanism at yard level where it is readily accessible for ease of maintenance and regulation of the feeding mechanism.

Preferably the bins are symmetrically arranged in the area of the feed end 21 of the belt 17 in two rows side by side and running transversely of the line of movement of the belt 17. The rows of bins are also preferably arranged, as shown in [FIGURES 2, 4 and 7, in tandem on opposite sides of the feed end 21 of the belt 17.

The surge hopper 21 is equipped with a gate 24 for use when dumping .bell No. l, to prevent the bell 25 from closing upon lump material.

One row of bins 23 comprises bins C for coke and bins L for limestone. Theother row of bins 23 comprises bins S for sinter and bins O for ore.

Sinter and coke are delivered to the stock bins S and C by means of separate belt conveyors 26, 27 and trippers 23, 29 which pivot on elements 28a, 29a, to tilt conveyors 26, 27 whereby the sinter or coke is dumped into the bin.

Limestone and screened ore are delivered to the stock bins L and O by means of one endless belt 31?, located between belts 2s and 27, but with double discharge trippers 31, 32 for limestone and ore. The double discharge tripper 31, 32, is pivoted on element 32a to dump material into bin L or O as desired.

Coke is withdrawn from the bins C by the action of vibratory screens 33 and is delivered to a coke weigh hop per 35 by means of a belt conveyor 34, which starts and stops concurrently with the screens 33. The coke Weigh hoppers 35 are hoppers that are also equipped with load cells (not shown) for automatic refilling and with air operated (not shown) gates 36 for discharging these hoppers in sequence to the feed end 21 of belt 17. Coke breeze passing through screens 33 is transferred by endless belt 51 to belt 22 which in turn delivers the breeze to a breeze bin 53 (FIG. 2) for storage.

Sinter is withdrawn from the bins S by the action of belt feeders 37 and is otherwise handled as described for coke by belt conveyor 38 which delivers to a sinter weigh hopper 39 that starts and stopsconcurrently with the belt fealers 37. The sinter wei h hoppers 39 are also equipped with load cells (not shown) for automatic refilling, and with air operated (not shown) gates at for discharging these hoppers in sequence to the feed end 21 of belt '17. A common type of air actuated control gate is described in US. Patent No. 2,603,342, issued July 15, 1962, and a common type of weigh hopper is described in US. Patent No. 2,750,144, issued June 12, 1956.

Screened ore and limestone, which are stored in bins O and L on each side of the centerline of the stockhouse, are withdrawn by means of belt conveyors or similar feeders 41, &2, which discharge to single weigh hoppers 43, 44 mounted on load cells (not shown) and equipped with air operated (not shown) gates 45, 46.

FIGURES 4, 5 and 6 show the basic arrangement of symmetrical stock for charge material proportions of 60 to lime and sinter and 4-0 to 20% screened ore. The combination of equipment as described is also suitable for a mixed charge system. .The number of bins can be modified to suit other proportions as required, or to provide additional storage capacity. The arrangement of parts as described for delivering either concurrently or in sequence of the various materials to the main belt 17, is primarily design for and adapted to operation by an electrical control system. Such a system may be of various well-knownones now in general use or readily devised, and those also shown in principle in many prior patents and illustrated by way of impressive schematic diagrams. Hence, no further detail illustration of the various control system that may be used in carrying out the present invention is necessary for an understanding of the same. A typical arrangement for sequential feeding of various materials is disclosed in US. Patent No. 2,873,955, patented February 17, 1959. Means such as that shown in this or other patents which are readily available can easily be adapted for use in the present invention.

The invention as hereinabove set forth is embodied in a particular form and manner of construction, but may be variously embodied within the scope of the following claims.

We claim:

1. A material handling system for layer filling material into the top hopper of a multiple superimposed sealable hopper charging mechanism at the top of a blast furnace, for operation therein at top pressure up to thirty pounds per square inch, comprising: a surge hopper equipped with gate mounted above atop hopper aforesaid for gravity feed to the top hopper without jamming the seal for the top hopper; a single endless belt conveyor having the major portion of its length inclined along a single line, devoid of transfer junctions, on an angle to the horizontal corresponding to the normal angle of repose of the material to be conveyed, from yard level up to a discharge position above said surge hopper, said conveyor having a lower, minor substantially horizontal feed portion disposed below yard level for feed of material to be conveyed thereto from feed equipment at yard level; a plurality of bins for ore, limestone and coke mounted above yard level in the area of said minor feed portion with bottom outlets above yard level for storage of said materials in position for conveyance to said minor feed portion; said bins being arranged symmetrically in two rows side by side and running transversely of the line of movement of said inclined belt conveyor With one row comprising bins for coke and limestone and the other row comprising bins for sinter and ore and in which the two rows of bins are arranged in tandem on opposite sides of said minor feed portion of the belt conveyor; and separate endless conveyor belts mounted over the respective rows of bins for separate delivery of Sinter to some of the bins in one row, and separate delivery of coke to some of the bins in the other row; a single endless belt conveyor with a double tripper mounted over the bins in the area between the aforesaid separate endless conveyor belts for separate delivery of limestone to another bin in the row containing the bins for coke, and for separate delivery of ore to another bin in the row containing the bins for sinter; separate coke and sinter endless conveyor belts at yard level and below the bottoms of the rows of bins for conveying coke and sinter to the feed end of the inclined endless belt conveyor; screening means for delivery of screened coke from a coke bin to the conveyor below its row; separate ore and limestone delivery means below the bottoms of the rows of bins for conveying ore and limestone to the feed end of the inclined endless belt conveyor; weigh hoppers for separately receiving coke, ore, limestone and sinter from their conveyor belts, weighing them, and then delivering them in sequence to the feed end of the aforesaid inclined endless belt conveyor.

2. A material handling system for layer filling material into the top hopper of a multiple superimposed sealable hopper charging mechanism at the top of a blast furnace, for operation therein at top pressure up to thirty pounds per square inch, comprising: a single endless belt conveyor having the major portion of its length inclined along a single line, devoid of transfer junctions, on an angle to the horizontal corresponding to the normal angle of repose of the material to be conveyed, from yard level up to a discharge position above said surge hopper, said conveyor having a lower, minor, substantially horizontal feed portion disposed below yard level for feed of material to be conveyed thereto from feed equipment at yard level, a plurality of bins arranged symmetrically in two rows side by side and each row extending transversely of the line of movement of said inclined belt conveyor, with one row comprising bins for coke and limestone and the other row comprising bins for sinter and ore, said rows of bins being mounted in tandem, above yard level, in the area of and on opposite sides of said minor feed portion with bottom outlets above yard level for storage of said materials in position for conveyance to said minor feed portion; and separate endless conveyor belts mounted over the respective rows of bins for separate delivery of sinter to some of the bins in one row, and separate delivery of coke to some of the bins in the other row; a single endless belt conveyor with a double tripper mounted over the bins in the area between the aforesaid separate endless conveyor belts for separate delivery of limestone to another bin in the row containing the bins for coke, and for separate delivery of ore to another bin in the row containing the bins for sinter; separate coke and sinter endless conveyor belts at yard level and below the bottoms of the rows of bins for conveying coke and sinter to the feed end of the inclined endless belt conveyor; screening means for delivery of screened coke from a coke bin to the conveyor below its row; separate ore and limestone delivery means below the bottoms of the rows of bins for conveying ore and limestone to the feed end of the inclined endless belt conveyor; weigh hoppers for separately receiving coke, ore, limestone and sinter from their conveyor belts, weighing them, and then delivering them in sequence to the feed end of the aforesaid inclined endless belt conveyor.

References Cited in the file of this patent UNITED STATES PATENTS 585,596 Rotthofi et al June 29, 1897 2,516,190 Dougherty et a1 July 25, 1950 FOREIGN PATENTS 145,507 Sweden June 1, 1954 1,193,485 France Apr. 27, 1959 

1. A MATERIAL HANDLING SYSTEM FOR LAYER FILLING MATERIAL INTO THE TOP HOPPER OF A MULTIPLE SUPERIMPOSED SEALABLE HOPPER CHARGING MECHANISM AT THE TOP OF A BLAST FURNACE, FOR OPERATION THEREIN AT TOP PRESSURE UP TO THIRTY POUNDS PER SQUARE INCH, COMPRISING: A SURGE HOPPER EQUIPPED WITH GATE MOUNTED ABOVE A TOP HOPPER AFORESAID FOR GRAVITY FEED TO THE TOP HOPPER WITHOUT JAMMING THE SEAL FOR THE TOP HOPPER; A SINGLE ENDLESS BELT CONVEYOR HAVING THE MAJOR PORTION OF ITS LENGTH INCLINED ALONG A SINGLE LINE, DEVOID OF TRANSFER JUNCTIONS, ON AN ANGLE TO THE HORIZONTAL CORRESPONDING TO THE NORMAL ANGLE OF REPOSE OF THE MATERIAL TO BE CONVEYED, FROM YARD LEVEL UP TO A DISCHARGE POSITION ABOVE SAID SURGE HOPPER, SAID CONVEYOR HAVING A LOWER, MINOR SUBSTANTIALLY HORIZONTAL FEED PORTION DISPOSED BELOW YARD LEVEL FOR FEED OF MATERIAL TO BE CONVEYED THERETO FROM FEED EQUIPMENT AT YARD LEVEL; A PLURALITY OF BINS FOR ORE, LIMESTONE AND COKE MOUNTED ABOVE YARD LEVEL IN THE AREA OF SAID MINOR FEED PORTION WITH BOTTOM OUTLETS ABOVE YARD LEVEL FOR STORAGE OF SAID MATERIALS IN POSITION FOR CONVEYANCE TO SAID MINOR FEED PORTION; SAID BINS BEING ARRANGED SYMMETRICALLY IN TWO ROWS SIDE BY SIDE AND RUNNING TRANSVERSELY OF THE LINE OF MOVEMENT OF SAID INCLINED BELT CONVEYOR WITH ONE ROW COMPRISING BINS FOR COKE AND LIMESTONE AND THE OTHER ROW COMPRISING BINS FOR SINTER AND ORE AND IN WHICH THE TWO ROWS OF BINS ARE ARRANGED IN TANDEM ON OPPOSITE SIDES OF SAID MINOR FEED PORTION OF THE BELT CONVEYOR; AND SEPARATE ENDLESS CONVEYOR BELTS MOUNTED OVER THE RESPECTIVE ROWS OF BINS FOR SEPARATE DELIVERY OF SINTER TO SOME OF THE BINS IN ONE ROW, AND SEPARATE DELIVERY OF COKE TO SOME OF THE BINS IN THE OTHER ROW; A SINGLE ENDLESS BELT CONVEYOR WITH A DOUBLE TRIPPER MOUNTED OVER THE BINS IN THE AREA BETWEEN THE AFORESAID SEPARATE ENDLESS CONVEYOR BELTS FOR SEPARATE DELIVERY OF LIMESTONE TO ANOTHER BIN IN THE ROW CONTAINING THE BINS FOR COKE, AND FOR SEPARATE DELIVERY OF ORE TO ANOTHER BIN IN THE ROW CONTAINING THE BINS FOR SINTER; SEPARATE COKE AND SINTER ENDLESS CONVEYOR BELTS AT YARD LEVEL AND BELOW THE BOTTOMS OF THE ROWS OF BINS FOR CONVEYING COKE AND SINTER TO THE FEED END OF THE INCLINED ENDLESS BELT CONVEYOR; SCREENING MEANS FOR DELIVERY OF SCREENED COKE FROM A COKE BIN TO THE CONVEYOR BELOW ITS ROW; SEPARATE ORE AND LIMESTONE DELIVERY MEANS BELOW THE BOTTOMS OF THE ROWS OF BINS FOR CONVEYING ORE AND LIMESTONE TO THE FEED END OF THE INCLINED ENDLESS BELT CONVEYOR; WEIGH HOPPERS FOR SEPARATELY RECEIVING COKE, ORE, LIMESTONE AND SINTER FROM THEIR CONVEYOR BELTS, WEIGHING THEM, AND THEN DELIVERING THEM IN SEQUENCE TO THE FEED END OF THE AFORESAID INCLINED ENDLESS BELT CONVEYOR. 